Flexible-printing-plate securing arrangement



- OctQZQ, 1963 J. T. BARNES 3,108,538

FLEXIBLE-PRINTING-PLATE SECURING ARRANGEMENT:

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\ gs JOSEPH T. BARNES .v 3. w m MV ATTORNEYS BYMAHONEY, MILLER SRAMBAO Oct. 29, 1963 J. T. BARNES 3,

FLEXIBLE-PRINTING-PLATE SECURING ARRANGEMENT I Filed Nov. 7, 1962 2 She ets-Sheet 2 2s 27 26 M I60 FIG-6 26b I69.

INVENTOR. T. BARNES BYMAHONEY, MILLER a RAMBO ATTORNEYS United States Patent Ofiice 3,168,538 FLEXIBLE-PRINTING-PLATE SECURING ARRANGEMENT Joseph T.'Barnes, 361 Oakland Park Ave,

Columbus, Ohio Filed Nov. 7, 1962, Ser. No. 236,011 2 Claims. (Cl. 101-4151) My invention relates to a flexible-printing-plate securing arrangement. It has to do, more particularly, with means for securing a flexible printing plate, such as a planographic plate, to a cylinder adapted to be rotated in the printing operation.

The invention may be applied to the plate cylinder of a printing press using an attachment of the type disclosed in my Patent No. 3,007,403 of November 7, 1961, although it is capable of application to many other plate cylinders; My invention is particularly applicable to a plate cylinder of the kind used in a letterpress and is such that it permits the mounting of the planograph plate on such cylinder. According to my invention, the printing plate is so applied to and secured to the cylinder that the forces created on the plate by the engagement of the impression cylinder therewith will tend to cause the plate to embrace the plate cylinder even more snugly.

For planographic printing, the printing plate sometimes comprises a relatively thin plate of sheet metal, such as aluminum, that is fastened to the surface of the plate cylinder. This invention is directed to a registration or attaching bar arrangement which may be attached to the usual letterpress-type plate cylinder to secure the planographic plate or similar plates thereto. This invention permits the press to be interchangeably set up for either letterpress operation or planographic operation in a minimum amount of time. With this arrangement, a letterpress-type plate which has been previously mounted on the cylinder may be removed and be replaced with a flexible planographic printing plate which is secured to the cylinder.

The accompanying drawings illustrate an embodiment of my invention and in these drawings:

FIGURE 1 is an isometric view showing a cylinder in a press having planographic printing plates mounted thereon according to my invention.

FIGURE 2 is an enlarged transverse sectional view taken at the location indicated at line 2-2 of FIGURE 1 and line 22 of FIGURE showing the attaching or registration bar assembly cooperating with the pianographic plates.

FIGURE 3 is an edge elevational view of the registration or attaching .bar assembly.

FIGURE 4 is a plan view of the lower member of the bar assembly.

FIGURE 5 is :an elevational view of the cylinder with the plates mounted thereon- FIGURE 6 is an axial sectional view taken along line 6-6 of FIGURE 5.

FIGURES 7 to 10 are diagrammatic views in end elevation showing the plate cylinder and the successive steps in applying the planographic plates thereto.

'FIGURE 11 is a diagrammatic view illustrating a printing press having a plate cylinder of a kind to which my invention may be applied.

With reference to the drawings, in FIGURE 11 I have illustrated a printing press having an attachment like that shown in my Patent No. 3,007,403 which is such that the press may be used as a letterpress or as a planographic press. In the drawing, II have shown a direct lithographic press where the paper W is fed in web form between an impression cylinder 15 and a plate cylinder 16. The necessary inking and ink pick-up apparatus, as described in said patent, is indicated generally at and supplies 3 ,103,538 Patented Oct. 29, 1963 ink to the cylinder 16. For letterpress operation, the cylinder 16 will have a type plate mounted thereon which will have raised letters or type in relief form. At this time, the water pick-up or dampening apparatus, de scribed in said patent and indicated generally at 10, will be disengaged from the form roller 18. When used as a lithographic press, the Water pick-up or dampening apparatus 10 will be engaged with the roller 18.

The plate cylinder 16 is constructed in the usual manner for a letterpress and is adapted to receive and retain the type plate, the one shown in the drawings being adapted to receive two plates axially aligned. When used as a letterpress, the plates mounted thereon are of cylindrical or tubular form and have a split or longitudinally extending slot. A bar (not shown) extending longitudinally of the cylinder and secured thereto cooperates with the slot in the plate to provide a registration index. A plurality of clamps are utilized to hold the plates on the cylinder. According to the persent invention, a similar cylinder is used in mounting either the relief plate or flexible planographic plate. However, since the flexible planographic plate is much thinner than the relief plate, a dummy plate must be used with the thin planographic plate as a filler when the combination planographic and dummy plate is substituted for the relief plate.

In FIGURES 1, 2, 5, and 6, I have indicated generally the construction of the plate cylinder '16 which is utilized for either letterpress or planographic printing operations. The plate cylinder is journalled at either end with bearings 25 suitably supported on the press (not shown) and is mechanically coupled through a gear train unit 25a (FIGURE 1) to the impression roll or cylinder 15 and the driving mechanism. At one end of the cylinder 16 (FIGURES 5 and 6) there are undercut clamping lugs 26 mounted thereon for cooperatively engaging the beveled end of either a relief plate or a dummy plate,

both of which are indicated generally by the numeral 16a.

At the opposite end of the plate cylinder 16, a fixed undercut clamping ring 26:: is provided for similarly engaging an adjacent end of a relief plate or a. dummy plate 16a. In this particular instance, a pair of relief plates or dummy plates 16a may be mounted on the plate cylinder 16. For this reason, a plurality of undercut center clamping lugs 26b are also provided for engaging the opposed beveled ends of the respective members 16a. The end clamping lugs 26 are mounted on rotatable, axially fixed, clamping rods or bolts 27 disposed in longitudinally extending slots formed in the periphery of the plate cylinder 16. Turning the clamping bolts 27 by means of a wrench engaging the squared ends 28 thereof will move the clamping lugs 26 longitudinally of the plate cylinder 16. The centerclamping lugs 26b are slidably mounted on the rods or bolts 27 and will be moved in accordance with the movable end clamping lugs 26. The detailed construction of the plate cylinder which is standard, is not of particular importance to this invention other than to indicate the clamping lugs and the clamping ring which are utilized to secure either the type plate or the dummy plate 16a to the plate cylinder 16.

My present invention deals primarily with the arrangement for locating and securing a planographic plate P or similar flexible plate to the cylinder 16 with dummy plates 16a thereon. This arrangement includes the longitudinally extending registration and attaching bar assembly 30 which is best shown in FIGURES 1 to 5.

The bar assembly 30 comprises a lower dummy plate loeating member 30a and an upper plate attaching rnem- 30b. These members are of sufiicient length to produce an assembly which will secure two of the planographic plates P and associated dummy plates 16a to the cylinder 16. The member 30 is of the construction illustrated in FIGURES 3 and 4 and is provided with a pair of recesses 31 in the upper surface on opposite sides of a central divider 31a, each of the recesses being adapted to receive one edge of a planographic plate P. The bottom surface of each recess is flat and there is a shoulder 32 at the inner or rear side of each recess, the recess being open at its outer or forward side. The member 30a is secured to a surface on the cylinder 16, which may be flattened, by means of countersunk screws 33 extending through the thick rear edge of the member and screws 34 extending through the thinner or recessed portion of the member. The screws 33 also secure the attaching member 3011 to the member 30a and the cylinder. This member 30b extends over the recesses 31 and rests on the central divider lug 31a of the member 30a. This member provides a free forward leading edge 35 for receiving the hooked edge 36 of the planographic plates P. It will be noted best from FIGURE 2 that the plate edge 36 is hooked to slip over the edge 35 of the member 3%. The member 30a is beveled at one end to provide a beveled surface 37 which fits under the undercut surface of the ring 26a.

Substantially no modification of the letterpress-type plate cylinder is required to attach this bar assembly 30 thereto. It is substantially of the same width as the usual registration bar and the bolt or screw holes are located in approximately the same positions. The thickness of this bar assembly and its length are the same as the bar usually provided on the cylinder when it is used as a letterpress cylinder.

In planographic printing operations, a dummy plate 16a is utilized with this bar assembly. The dummy plate also has a wall thickness greater than the height of the bar, but the thickness thereof 'will be less than that of the letter-type cylinder. The difference in thickness will be equal to the thickness of the planographic plate P. Thus, whichever type of printing is desired, the surface of the letter-type cylinder or the planographic plate 160 will be of the same distance from the plate cylinder to properly engage the impression roll or cylinder 15. The leading edges of each of the dummy plates 16a will engage the stop or member 30a whereas its trailing edge will be spaced therefrom to permit expansion as shown best in FIGURE 2.

The attachment of the planognaphic plate P is best shown in FIGURES 7 to 1 0. This edge or hook 36 of the planographic plate is placed over the member 30b, as indicated in FIGURE 7. The planographic plate is then wrapped around the plate cylinder as indicated in the successive FIGURES 8 and 9 and the trailing edge is finally pushed into the respective recess 31 beneath the bar or member 30b. Preferably, there will be a space between the trailing edge of the plate and the vertical wall or shoulder 32 of the bar 300. With this type of bar assembly, rotation of the plate cylinder 16 will continuously force the trailing edge of the planographic plate P farther into the recess of the bar assembly since it is free to move relative thereto. The resiliency of the plate P itself, which is bent when inserted into the recess 31, aids in keeping it in the recess.

It will be apparent from the above that this invention provides a bar assembly for attaching a flexible plate to a plate cylinder. This assembly can be substituted for the usual bar provided on the cylinder when it is used in a letterpress printing operation. Therefore, when the press has an attachment like that disclosed in my patent, it can be used as a letterpress or a flexible plate press and the plate mounted on the cylinder can be a letterpress-type plate or a flexible plate as desired. When the bar assembly secures the flexible plate to the cylinder, it does so in such a manner that tension created on the plate during the printing operation will more firmly engage the hook thereof with the attaching bar and cause the plate to more tightly embrace the dummy plate carried by the cylinder.

According to the provisions of the patent statutes, the principles of this invention have been explained and have been illustrated and described in what is now considered to represent the best embodiment. However, it is to be understood that, Within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

Having thus described my invention, what I claim is:

1. In combination with a plate cylinder for use in printing, an attaching bar extending across the cylinder and being secured thereto, a dummy plate on the cylinder having edges on opposite sides of the bar, said bar having an attaching free leading edge and a recess below the edge opening at said edge at a level below the outer surface of the dummy plate, a flexible plate wrapped around the dummy plate on the cylinder having a hook-shaped leading edge which fits around said free leading edge of the bar, said plate also having a free trailing edge which extends into said recess and tucks under the free leading edge of the bar with the hooked plate edge thereon whereby said trailing edge may move relative to said bar.

2. In combination with a plate cylinder for use in printing, an attaching bar assembly extending across the cylinder, said bar assembly comprising an inner bar secured to the cylinder, an outer bar secured to the inner bar and having its leading edge free and spaced outwardly from the inner bar to provide a slot therebetween opening toward said leading edge, a dummy plate on the cylinder having edges on opposite sides of the bar assembly and having one edge engaging the inner bar at its trailing edge and having its other edge spaced from the leading edge of the outer bar, said bar assembly being of less thickness than the dummy plate, a flexible plate wrapped around the dummy plate on the cylinder having a hook-shaped leading edge which fits around said free leading edge of the bar, said plate also having a free trailing edge which extends inwardly over the trailing edge of the dummy plate and into said slot beneath said outer plate and being free to move relative to said plate.

References Cited in the file of this patent UNITED STATES PATENTS 2,186,764 Meisel Jan. 9, 1940 2,621,592 Faeber Dec. 16, 1952 2,900,904 Hantscho Aug. 25, 1959 2,970,540 Wirth Feb. 7, 1961 3,008,410 Bryer Nov. 14, 1961 3,016,010 Luehrs Jan. 9, 1962 

1. IN COMBINATION WITH A PLATE CYLINDER FOR USE IN PRINTING, AN ATTACHING BAR EXTENDING ACROSS THE CYLINDER AND BEING SECURED THERETO, A DUMMY PLATE ON THE CYLINDER HAVING EDGES ON OPPOSITE SIDES OF THE BAR, SAID BAR HAVING AN ATTACHING FREE LEADING EDGE AND A RECESS BELOW THE EDGE OPENING AT SAID EDGE AT A LEVEL BELOW THE OUTER SURFACE OF THE DUMMY PLATE, A FLEXIBLE PLATE WRAPPED AROUND THE DUMMY PLATE ON THE CYLINDER HAVING A HOOK-SHAPED LEADING EDGE WHICH FITS AROUND SAID FREE LEADING EDGE OF THE BAR, SAID PLATE ALSO HAVING A FREE LEADING EDGE OF EXTENDS INTO SAID RECESS AND TUCKS UNDER THE FREE LEADING EDGE OF THE BAR WITH THE HOOKED PLATE EDGE THEREON WHEREBY SAID TRAILING EDGE MAY MOVE RELATIVE TO SAID BAR. 